An α-sulfofatty acid ester salt (hereinafter, sometimes referred to as “α-SF salt”) which is an anionic surfactant has high detergency and favorable biodegradability, and is used as a cleaning component for various detergents.
For example, a liquid detergent containing an α-SF salt, soap, and an ethylene oxide adduct of a higher fatty alcohol has been proposed (refer to PTL 1).